Fix document widget selectors
Fix document widget selectors

TypeFox/jupyterlab,jupyter/jupyterlab,charnpreetsingh185/jupyterlab,eskirk/jupyterlab,charnpreetsingh185/jupyterlab,eskirk/jupyterlab,jupyter/jupyterlab,TypeFox/jupyterlab,eskirk/jupyterlab,jupyter/jupyterlab,TypeFox/jupyterlab,eskirk/jupyterlab,jupyter/jupyterlab,charnpreetsingh185/jupyterlab,charnpreetsingh185/jupyterlab,jupyter/jupyterlab,TypeFox/jupyterlab,TypeFox/jupyterlab,eskirk/jupyterlab,charnpreetsingh185/jupyterlab